michael@0: // A for-of loop over an array does not take a snapshot of the array elements.
michael@0: // Instead, each time the loop needs an element from the array, it gets its current value.
michael@0: 
michael@0: var a = [3, 5, 5, 4, 0, 5];
michael@0: var s = '';
michael@0: for (var i of a) {
michael@0:     s += i;
michael@0:     a[i] = 'X';
michael@0: }
michael@0: assertEq(s, '355X0X');